Change proxy after x many loops

I have a list of let's say 100 URLS.
I want to change IP after every 10 URLS.

Let's say I have my own proxies that I'd like to use after each 10 URLS.
How would I use that proxy in my requests - ?

list = [100URLS items]
proxies ['ip:port','ip:port']
for urls in list:
try:
##request 10 URLS here then it might throw me error.
except:
#After it throws me error, I want to be able to use proxies inside a list something like this and reiterate the same request with a new proxy using requests.